It’s something I get every year, especially with a last name that’s more Irish than a spraypainted sheep.  It’s easier to just explain it this way.

• St. Patrick’s Day is not merely a Christian holiday; it celebrates a Christian victory over paganism. I’m not a druid (though some of my dear friends are), but I am a Germanic Heathen–thus more akin than not. I don’t think it’s anti-Christian to say I can hardly cheer for its vanquishing of indigenous beliefs. For me to celebrate this would be like UCLA fans getting together to remember and celebrate all the times USC beat them. In what universe would I be glad for this?
• It’s more an Irish-American holiday than an Irish holiday. I have that on good authority from the Irish themselves, who surely are greater authorities on Irishness than Irish-Americans. One Irishwoman told me about her horror at an Irish festival in California, watching people collect money for ‘the struggle.’ She called them ‘the shamrock people.’ Remember, these are her words, not mine. Her further comment:  “Either the shamrock people are Irish, or I am, but we both can’t be.”
• Because of that, what you get is millions of people going as overboard as possible on what they see as Irishness: leprechauns, green beer, green stripes on roads, green clothing, red hair, freckles, alcoholism, and so on. There are bits of truth in that, sure, but it’s not how I see Ireland. I see Irishness as hospitality after a brief period of caution, eagerness to talk to strangers, a passion for all arts (musical, literary, visual), and yes, a history of suffering and in some cases terrible violence. Leon Uris got it right: a terrible beauty. To me, St. Patrick’s Day doesn’t look very Irish. As an editor, even if I were not part Irish, anyone sending me a manuscript full of stereotypes would enjoy a flood of margin comments.
• Speaking of alcoholism, do we really need to push that stereotype harder? In the past, it was part and parcel of oppressive stereotyping by the British occupiers (and the Americans who looked down upon Irish immigrants: the drunken Mick, face shaped in simian fashion, feckless, slumped in an alley, presented as proof that Irish were a lower form of life. Here’s one for you: alcoholism in Ireland has all the same consequences it has in the United States. Shortened lives, failed commitments, bad decisions, battered wives, beaten kids, damaged families, avoidable road fatalities, cirrhosis, addiction battles, stupid sayings, and so on. It might seem funny from here, maybe not so much so if you think about the families it harms. If a foreign country celebrated July 4 with parodies of random school shootings, would that amuse us?
• What of the Irish whom the orange bar on the flag represents? They are Protestants. They too are Irish; their relatives also emigrated here. How can they be left out? How can one think this will help promote unity in the old country? If you care about Ireland, how can you not want its differing faiths and ethnicities to get along, united in Irishness? St. Patrick’s Day claims to represent all things supposedly Irish, and all the Irish groups make a big deal of non-sectarianism. Ask an Ulster Protestant how really part of it she feels. When she does feel like part of it, it’ll be a win.
• Finally, I’m not much moved by part-time Irishness. Therefore I am prone to say: “Tell you what. I understand some Irish (Gaelic). If you can lecture me in Irish as to why I should wear green, I may not do it, but I will hear you out. If you want to get down with your bad Irish self, study the Irish language in all its complexity and beauty. And when you do, and you want to pressure me about this, we will have that discussion. In Irish.  Until then, I’ll pass, thanks.”

Not to be a stick in the mud, though. If you’re observing the holiday, have a happy one. Honestly.